Blu-ray or Blu-ray Disc is a digital optical disc data storage format. It was designed to supersede the DVD format, in that it is capable of storing high-definition and ultra high-definition video resolution . The plastic disc is 120mm in diameter and 1.2mm thick, the same size as DVDs and CDs Conventional Blu-ray Disc discs contain 25 GB per layer, with dual layer discs being the industry standard for feature-length video discs. Triple-layer discs and quadruple-layers are available for BD-XL re-writer drives. The name "Blu-ray" refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs. The main application of Blu-ray is as a medium for video material such as feature films and physical distribution of video games for the PlayStation 3, PlayStation 4, and Xbox One Besides the hardware specifications, Blu-ray is associated with a set of multimedia formats.